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name: streamlit-dashboards description: "It guides a later agent through composing Streamlit multipage dashboards, validating local data contracts, joining U.S. housing metrics to geographies, comparing historical tile layers, and deploying safely without mutating the host." disable-model-invocation: true metadata: disco-role: operating license: MIT

Streamlit dashboards

Use this sub-skill when the task is to build or repair the app shell, a data-backed U.S. housing view, or a historical Ordnance Survey comparison in the streamlit-geospatial operating graph.

Route first

• For Home.py and pages/ composition, follow dashboard-workflows.md.
• Before joining a local CSV to a boundary file, apply data-contracts.md and run the bundled dashboard input validator.
• For deployment failures or unsafe host mutation, use troubleshooting.md.
• Route low-level Leafmap/Folium map API questions to interactive-maps. Route Earth Engine questions to remote-geospatial-data.

Operating guardrails

1. Treat remote housing and tile endpoints as versioned, drift-prone inputs. Do not assume a successful HTTP response has the expected schema or that every selected period has a matching geography.
2. Keep identifiers as strings during ingestion. Preserve leading zeroes for county FIPS and postal codes, and report unmatched or null geometry rather than silently coercing it into a map.
3. Use the validator for deterministic local checks only. It performs no remote downloads and writes only when an explicit --output path is supplied.
4. Keep the Streamlit app's working-directory assumptions explicit. Prefer an app-root-derived path in new code; do not make a shared host's home configuration part of deployment.
5. Keep the dashboard router-like: select the page workflow, data contract, and recovery path, then load only the reference needed for that branch.